Samia Shahid, from Bradford, died while visiting her family in Pakistan.
Photograph: Supplied

Family members accused of killing Samia Shahid, a British citizen who divorced and remarried without their permission, planned to use Pakistan’s much-criticised “blood money” laws to forgive her killer, a report into the case has alleged.

Police findings say the 28-year-old was the victim of “premeditated and cold-blooded honour killing”, which her family had hoped to get away with by exploiting Islamic laws the government has repeatedly promised to scrap.

A 43-page document says her father, Mohammad Shahid, asked for a postmortem examination to be carried out on his daughter two hours after helping her first husband, Mohammad Shakeel, strangle her to death in the family’s ancestral village of Pandori, in the state of Punjab, on 20 July.

Police say he wanted to rush the investigation, which was likely to conclude from bruising around Samia Shahid’s neck that she had been murdered, so he could lodge a criminal case against Shakeel. “If Shakeel had been charged for murder … [Mohammad] Shahid could have easily pardoned him after a few days, being ‘wali’ [guardian] of the victim,” the report said.

Under Pakistan’s 25-year-old blood money laws, the guardians of murder victims can forgive their killers in return for compensation, even though family members often conspire with each other to commit such crimes.

Rights campaigners say the effective impunity created by the laws has helped fuel the problem of so-called “honour killings”. There were more than 1,000 such killings reported to police last year, although the real number is thought to be far higher.

The document was provided to the Guardian by Abubakar Khuda Bakhsh, appointed to lead a special investigation into the case for Punjab police after the Bradford MP Naz Shah appealed to Pakistan’s prime minister, Nawaz Sharif.

The report will be among documents due to be submitted on 17 September at the formal start of Mohammad Shahid’s trial.

Mohammad Arif, Shahid and Shakeel’s lawyer, said his clients would plead not guilty.

The police report said the men could have successfully “hidden this gory crime in almost a perfect plot” were it not for the arrival in Pakistan the next day of Samia Shahid’s second husband, Mukhtar Syed Kazam, who immediately filed a criminal complaint against the family. Samia’s father had attempted to conceal from police that his daughter had divorced Shakeel, a first cousin who had once been charged with attempted murder.

The report said the family felt “dishonoured” by the divorce that she had organised in a Bradford sharia court in 2012 after a brief and unhappy marriage she claimed was never consummated. The divorce also angered Shakeel because it deprived him of the opportunity to immigrate to the UK and become a British citizen, the report said.

Samia’s decision to then marry a man from outside her extended family, who as a Shia did not follow the same Sunni school of Islam, had “further tarnished the honour of the family”.

According to the report, Shakeel and Shahid hoped that once Samia was in Pakistan they could persuade her to abandon her second husband and return to Shakeel. Otherwise, Shahid was “determined to go to any extent including taking [his] daughter’s life”, the report said.

The report said Samia was sufficiently worried about her security not to tell her family when she was arriving and to arrange to be collected from the airport by a childhood friend, with whom she left her passport and return ticket as a safety measure.

The report said they decided to kill her the day before she was due to return to Dubai, having failed to persuade her to stay in Pakistan.

Shakeel was said to have confronted Samia in an upstairs bedroom of his large house in Pandori and demanded to know where her passport and return ticket were. After she refused to tell him, he attacked and raped her, the report said.

While trying to leave the house and threatening to alert the British government, she was confronted on the stairs by her father, it was claimed. Shakeel then strangled her with a scarf while her father held her legs, the report said.

Arif told the Guardian: “Confessions made before the police have no legal value here in Pakistan.”

Pakistan’s government has won international plaudits by repeatedly promising to reform the blood money laws in a move that could trigger angry opposition from some hardline clerics. Sharif promised to take action in February after a Pakistani documentary about “honour killings” was nominated for an Oscar.

Sughra Imam, a former senator who has campaigned for years to change the laws, said there had been “consistent foot dragging” on the issue. “We should strike while the iron is hot, but unfortunately the government seems to lack a sense of urgency,” she said. “It is regrettable because meanwhile lives are being lost.”